Predictors of survival after trimodality therapy for esophageal adenocarcinoma: Analysis from the National Cancer Database.

Abstract

116 Background: Trimodality therapy with neoadjuvant chemoradiation followed by surgery has been shown to improve survival compared to surgery alone for the treatment of locally advanced esophageal cancer, but there is considerable variation in survival in this population. We sought to analyze factors associated with survival after trimodality therapy in esophageal adenocarcinoma. Methods: We identified 4,679 patients from the National Cancer Database (NCDB) who received chemotherapy and radiation prior to surgery for esophageal adenocarcinoma from 2006-2013. Patients with stage IV disease and unknown pathological nodal status were excluded. We performed a multivariate analysis using a Cox proportional hazards model to identify independent predictors of overall survival. Results: On multivariate analysis, pathologic characteristics associated with decreased overall survival included stage, lymphovascular invasion, and positive surgical margins. Insurance status, age, and comorbidity index were also associated with decreased survival. We found that patients treated at academic programs (HR 0.85, CI 0.78-0.92, p=0.0001) and those who received additional adjuvant chemotherapy had improved survival (HR 0.86, CI 0.75-1.00, p=0.0452), but the vast majority of patients receiving trimodality therapy (4,306; 92.0%) did not receive adjuvant chemotherapy. Patients who received adjuvant chemotherapy were more likely to have private insurance (69 vs. 53%, p<0.0001). Compared to private insurance, Medicaid (HR 1.43, CI 1.20-1.70, p<0.0001), Medicare (HR 1.21, CI 1.07-1.36, p=0.0026), or having no insurance (HR 1.49, CI 1.16-1.90, p=0.0015) were all negative predictors of overall survival. Conclusions: There is wide variation in survival following trimodality therapy for esophageal adenocarcinoma. Both tumor characteristics and patient characteristics play a role. Adjuvant chemotherapy appears to be associated with improved survival, but only a minority of patients receive adjuvant chemotherapy in this setting. Insurance status and treatment setting are independent predictors of overall survival after trimodality therapy and may indicate treatment disparities.